The present invention relates to a new and distinct hybrid of Geum plant named ‘Gimlet’ characterized by semi-double to single flowers that open yellow and fade to light yellow with creamy white tips. The new Geum was developed as a seedling as part of an on going breeding and selecting program, in Hebron, Ill. in 2008. The parents of the new plant are unknown. The selection of the new plant was due to its' semi-double to single flowers that open yellow and fade to light yellow with creamy white tips. The initial asexual propagation of the new plant was by division and took place at a nursery in Hebron, Ill. in 2009. Continued asexual propagation by division since that time has shown that the unique features of this new Geum plant are stable and reproduced true to type in successive generations.